关键词: 粗糙元, 转捩, T-S波

Abstract: An experimental investigation on the transition in the boundary layer of horizontal plane with and without single two-dimensional roughness elements has been carried out in the wind tunnel. The distribution in normal and stream-wise directions of intensity of T-S wave excited by vibrating beam was measured in every condition. Neutral curves were obtained by measuring the growth of the T-S wave at the normal critical location along the stream-wise direction. Comparing with the neutral cave on the smooth plane that was thumb-like and opened at the bottom, the neutral caves on the plane with single roughness elements were closed circles. With the growing of roughness element's height, the closed circle became smaller.

Key words: roughness elements, boundary-layer transition, T-S wave